• Korean Journal of Logic
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• v.15 no.3
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• pp.375-392
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• 2012

In a previous paper I argued that the denial of the uncontested principle results in the denial of modus ponens. In his reply Byeong Deok Lee explicitly says that he does not deny the validity of modus ponens though he still does not accept the uncontested principle. In this paper I show that his view is untenable.

• Korean Journal of Logic
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• v.17 no.1
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• pp.197-217
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• 2014

In my previous papers, I have argued that the so-called 'Uncontested Principle' does not hold for indicative conditionals based on inductive reasoning. This is mainly because if we accept that a material conditional '$A{\supset}C$' can be inferred from an indicative conditional based on inductive reasoning '$A{\rightarrow}_iC$', we get an absurd consequence such that we cannot distinguish between claiming 'C' to be probably true and claiming 'C' to be absolutely true on the assumption 'A'. However, in his recent paper "Uncontested Principle and Inductive Argument", Eunsuk Yang objects that my argument is unsuccessful in disputing the Uncontested Principle. In this paper, I show that his objections are irrelevant to my argument against the Uncontested Principle.

• Korean Journal of Logic
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• v.15 no.3
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• pp.323-347
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• 2012

After Byeongdeok Lee(2008) argued against the so-called uncontested principle (UP), Song(2008) and Choi(2011) gave arguments against Lee(2008) and instead for UP. One important point to mention in their arguments is that they all accept that UP is justifiable in deduction. First, I show that there are some problems in their arguments. Next, I show that UP itself is not justifiable in deduction; it is only justifiable under some (restrictive) conditions.

• Korean Journal of Logic
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• v.15 no.2
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• pp.273-294
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• 2012

In my previous article "An Inferentialist Account of Indicative Conditionals" and "An Inferentialist Account of Indicative Conditionals and Hasuk Song's Objections", I argued that the so-called Uncontested Principle is not uncontestable. According to the Uncontested Principle, an indicative conditional '$A{\rightarrow}C$' logically implies a material conditional '$A{\supset}C$'. In his recent paper "On the Recent Controversies surrounding the Uncontested Principle" Wonbae Choi presents three objections to my claim. First, my denial of the Uncontested Principle implies rejecting modus ponens. Second, my denial of the Uncontested Principle is tantamount to taking the truth-conditions of an indicative conditional as weaker than those of a material conditional, which are usually taken to be the weakest among conditionals. Third, my view that we can warrantedly assert '$A{\rightarrow}C$' even when 'A ${\therefore}$ C' is inductively justified is based on a misunderstanding of the way in which indicative conditionals are justified. In this paper I argue that Choi's objections are all based on misunderstandings of my view. First, I do not deny the validity of modus ponens (as a form of deductive reasoning). Second, the fact that the inductive warrantability of 'A ${\therefore}$ C' does not imply the truth of '$A{\supset}C$' does not show that the truth-conditions of an indicative conditional is weaker than those of a material conditional. Third, Choi's claim that a contingent conditional '$A{\rightarrow}C$' is true only when 'C' can be deductively derived from 'A' in conjunction with a hidden premiss is not well grounded, nor does it fit the facts.

• Korean Journal of Logic
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• v.14 no.3
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• pp.85-100
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• 2011

Recently Byeong Deok Lee has denied the validity of the so-called uncontested principle, which says that the indicative conditional implies the material conditional. I show that his denial means that modus ponens is not valid and that the truth-conditions of indicative conditionals are weaker than that of material conditionals. It seems that what made him hold this view is related to some misunderstanding of indicative conditionals.

• Korean Journal of Logic
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• v.16 no.1
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• pp.87-115
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• 2013

In my previous article "The Uncontested Principle and Wonbae Choi's Objections", I argued that the validity of modus ponens (as a deductive inference) is compatible with the claim that the Uncontested Principle is controversial. In his recent paper "The Uncontested Principle and Modus Ponens", Wonbae Choi criticizes my view again by making the following three claims: First, even though I do not take an inference of the form 'If A then (probably) C. A. $\therefore$ C' as an instance of modus ponens, this form of inference can be taken to be such an instance. Second, there is no grammatical indicator which allows us to distinguish between an indicative conditional based on a deductive inference and an indicative conditional based on an inductive inference, so that inferences based on these conditionals should not be treated as different types of inferences. Third, if we allow an indicative conditional based on an inductive inference, we thereby violate the so-called 'principle of harmony', which any logical concept should preserve. In this paper, I reply that his criticisms are all implausible.

• Korean Journal of Logic
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• v.12 no.2
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• pp.31-58
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• 2009

This paper defends Stalnaker's theory of indicative conditionals. His theory consists of selection functions and pragmatic constraints. The selection function takes a certain possible world(W) and a proposition(A) to yield a possilble world that is similar to W and in which A is true. And the pragmatic constraints plays role to make selection functions apply just to indicative conditionals. According to Stalnaker, as indicative conditionals has strong truth-value, uncontested principle always holds but passage principle does not always hold. However, his theory can explain why passage principle sometimes holds by means of pragmatic constraints. Also, this paper argues that Stalnaker's theory is the most acceptable one among others, by replying to criticisms suggested by Adamsians and the problem raised by Gibbard and other criticisms.